If your gonna get a smaller pulley, you will need supporting cooling mods. Wouldn't go any lower than a 2.6. If you do go that low though, I'd recommend Meth inj, bigger HE, and Dual Pass. Definitely gonna need bigger injectors and exhaust.
Cheaper route is to get a stage II kit. Check with ZZP to get staging ideas
O T T P TVS Stage 3 w/ 2.9" & 80# inj., ZZP 3" CAI, ZZP Stainless Mid-Length Header w/ 3" Catted DP, ZZP Stainless 3" Magnaflow Cat-Back, O T T P Heat Exchanger, Opt B, TTR Upper Engine Mount